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Biodegradable,superhydrophobic walnut wood membrane for the separation of oil/water mixtures

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Frontiers of Chemical Science and Engineering 2022年第9期16卷 1377-1386页

作者： Tong Xing changqing dong Xiaodong Wang Xiaoying Hu Changrui Liu Haiyang Lv National Engineering Laboratory for Biomass Power Generation Equipment School of New EnergyNorth China Electric Power UniversityBeijing 102206China State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China National Energy Biological Power Generation Group Corporation LTD Beijing 100052China

The preparation of environmentally friendly oil/water separation materials remains a great ***-drying of wood after lignin removal yields wood aerogels,which can be used as substrates to prepare fluorine-free environmentally friendly superhydrophobic materials,However,they are more suitable for absorption rather than filtration applications due to their poor strength.A study using cross-sections of pristine wood chips as substrates retains the original strength of wood,but the use of the cross-sectional of wood pieces limits their thickness,strength,and *** this paper,a degradable fluorine-free superhydrophobic film(*** contact angle of approximately 164.2°)with self-cleaning and abrasion resistance characteristics was prepared by a one-step method using pristine and activated walnut longitudinal section films as the substrate,with tetraethyl orthosilicate as a precursor and dodecyltriethoxysilane as a *** tensile strength results show that superhydrophobic films with pristine or activated wood substrates maintained the strength of pristine wood and were 2.2 times stronger than the wood aerogel *** addition,after cross-laminating the two samples,the films had the ability to separate oil and water by continuous filtration with high efficiency(98.5%)and flux(approximately 1.3×10^(3)L∙m^(‒2)∙h^(‒1)).The method has potential for the large-scale fabrication of degradable superhydrophobic filtration separation membranes.

关键词： wood nanotechnology superhydrophobic biodegradable surface modification oil/water separation

The effect of biomass pyrolysis gas reburning on N_2O emission in a coal-fired fluidized bed boiler

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Chinese Science Bulletin 2011年第14期56卷 1429-1433页

作者： HU XiaoYing dong changqing YANG YongPing ZHANG JunJiao National Engineering Laboratory for Biomass Power Generation Equipment North China Electric Power University Beijing 102206 China

The fossil fuel consumption and pollutant emissions in a coal fired fluidized bed boiler could be reduced by biomass pyrolysis gas *** influence of three kinds of biomass pyrolysis gases on the emission of N_2O in a laboratory scale fluidized bed was investigated using the mechanism of GRI3.0 in this *** results showed that:the effect of sawdust pyrolysis gas reburning on N_2O was more significant than that of rice husk and orange peel under the same conditions;the increase of initial oxygen content from 1% to 8% in flue gas would restrain the decomposition of N_2O;the N_2O decomposition was enhanced by increasing reaction temperature from 1073.15 K to 1323.15 K,and the decomposition rate may reach 99% at 1223.15 K.

关键词： N2O排放生物质热解流化床锅炉气体再燃燃煤 N2O分解实验室规模燃料消耗

Evaluation of solar aided biomass power generation systems with parabolic trough field

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Science China(Technological Sciences) 2011年第6期54卷 1455-1461页

作者： HOU HongJuan YANG YongPing HU Eric SONG JiFeng dong changqing MAO Jian Beijing Key Laboratory of Safe and Clean Energy Technology North China Electric Power University Beijing 102206 China National Engineering Laboratory for Biomass Power Generation Equipment North China Electric Power University Beijing 102206 China School of Mechanical Engineering The University of Adelaide SA 5005 Australia

Solar and biomass are both renewable energy *** biomass as fuel is becoming more and more attractive after governments increase the tariff for the electricity from the renewable *** the costs of power from a biomass power generation plant depend greatly on the availability and quality of the biomass *** commercialization of solar alone thermal power generation is hindered by its high initial investment and low thermal *** this paper,a concept of integrating solar into a biomass power generation system is put *** the system the oil heated by a parabolic trough solar field is used to replace the extraction steam to preheat the feed water(entering a biomass boiler) and the previous extraction steam thus saved can continue to do work in the lower stages of *** performance of the hybrid system with different replacements is analyzed and compared through two typical solar aided biomass generating *** results show that the integration not only reduces the consumption of biomass fuel(at the same generation capacity) but is also proved to be an efficient way to convert solar thermal energy into *** results also show that with the same solar aperture area,the higher the grade of the replaced extraction steam,the better the thermal performance and economy.

关键词： solar thermal power biomass power aided

Pretreatment mechanism ofβ-O-4 lignin during phosphoric acid-acetone process based on density functional theory and molecular dynamic simulations

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International Journal of Agricultural and Biological Engineering 2016年第2期9卷 127-136,I0004页

作者： Zhang Junjiao Zhu Jinqi Lin Changfeng Wang Tipeng dong changqing Qin Wu National Engineering Laboratory for Biomass Power Generation Equipment School of Renewable EnergyNorth China Electric Power UniversityBeijing 102206China

Pretreatment mechanism ofβ-O-4 lignin(Lβ-O-4)during the phosphoric acid-acetone process involves a series of interactions between lignin and solvent molecule(H2O,CH3COCH3 and H3PO4)which lead to the adsorption,solubility and decomposition of *** alcohol guaiacyl glycerol(CAGG)with the predominant linkage(β-O-4 ether bond)was chosen as the modelβ-O-4 lignin(Lβ-O-4)for investigating the detailed pretreatment mechanism based on density functional theory calculations and molecular dynamic *** betweenβ-O-4 lignin and solvent molecules were firstly *** physical interaction occurred betweenβ-O-4 lignin and the solvent *** attractive van der Waals interaction favored CH3COCH3 molecules approaching to Lβ-O-4,showing a compatibility of Lβ-O-4 in CH3COCH3 ***,following the temperature effect on the dynamics processes,larger dynamics calculations and experiments were carried out to reveal the detailed dissolution and precipitation ofβ-O-4 lignin in various solutions.

关键词： lignin lignocellulose biomass pretreatment density functional theory(DFT)

Optimal adoptions of freemium version and patching strategy:Network and security externalities

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Journal of Management Science and Engineering 2022年第1期7卷 107-132页

作者： Nan Feng Hanyue Zhang changqing dong Jie Zhang Minqiang Li Jing Xie College of Management and Economics Tianjin UniversityTianjin300072China College of Business Administration University of Texas at ArlingtonArlingtonTX76019USA

The freemium pricing model has become mainstream in the software industry.A large user base can induce positive network effects while expanding security risks associated with unpatched *** study explores a two-stage decision problem faced by software vendors that involves a freemium versioning strategy and a subsequent security-patching strategy when taking both the positive network externality and negative security externality into *** is noteworthy that a joint effect of the two externalities on the vendor’s management decisions ***,we analytically derive three patching strategies for the vendor:PS_(1)(rebates all users),PS_(2)(rebates only freeware users),and PS_(3)(rebates no users).Our results indicate that,if the strength of the positive network externality is relatively low,the optimal security-patching strategy will be significantly affected by the negative security ***,when the intensity of the negative security externality is low,the vendor’s optimal patching strategy will be PS_(1).However,with the increase in the negative security externality,the optimal patching strategy changes to PS_(2) and then to PS_(3),whereas the strategy spaces of PS_(1) and PS_(2) decrease in the positive network externality to ***,if the strength of the positive network externality is relatively high,the vendor is better off selecting PS_(1) when the negative security externality is ***,when the negative security externality is high,PS_(3) is ***,based on optimal patching strategies,we reveal the optimal conditions required for the vendor to adopt the freemium model compared with commercial *** interest,we find that the vendor adopting the freemium version is also influenced by the interaction of the two ***,through numerical experiments,we find that the vendor and social planner’s interests can be aligned under certain ***,this is not always the case.

关键词： Freemium Positive network externality Negative security externality Patching strategy

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生物质燃烧和热解中钾的释放规律研究进展

化工进展 2020年第4期39卷 1292-1301页

作者：王洋董长青中国华能集团有限公司生产环保部北京100031 华北电力大学可再生能源学院北京102206

生物质中碱金属钾的含量较高,钾在燃烧和热解过程中释放到炉内,会造成积灰、结渣、腐蚀等问题,影响锅炉安全、经济运行。本文通过对文献进行比较和分析,介绍了生物质中钾的含量和赋存形式,碱金属的定量检测方法,生物质中钾在不同条件下... 详细信息

生物质中碱金属钾的含量较高,钾在燃烧和热解过程中释放到炉内,会造成积灰、结渣、腐蚀等问题,影响锅炉安全、经济运行。本文通过对文献进行比较和分析,介绍了生物质中钾的含量和赋存形式,碱金属的定量检测方法,生物质中钾在不同条件下热解和燃烧过程中的释放规律,以及燃料成分和粒径、反应温度和升温速率、反应器类型等因素对钾释放规律的影响。结果表明,生物质燃料中钾的赋存形式包括有机钾、无机钾和含钾矿物质等;有机钾分解所释放出的一次产物,最终会经过不同路径的二次反应以其他形式释放或留在灰中;钾的最终释放形式与释放过程中发生的二次反应密切相关,主要包括KCl、K2SO4、KOH和含钾矿物质。

关键词：生物质燃烧热解钾释放

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波纹环气膜冷却结构燃烧室壁温计算

西北工业大学学报 1988年第1期6卷 53-61页

作者：朱长青董志锐西北工业大学西北工业大学教授讲师

本文用数值方法计算采用波纹环气膜冷却结构的燃烧室的壁温分布和热流分布。由于本文在壁温计算方法上做了较大的改进,计算出的壁温分布曲线与实测壁温分布曲线相当吻合。本文提出的数值计算方法和计算机程序可用于波纹环气膜冷却结构... 详细信息

本文用数值方法计算采用波纹环气膜冷却结构的燃烧室的壁温分布和热流分布。由于本文在壁温计算方法上做了较大的改进,计算出的壁温分布曲线与实测壁温分布曲线相当吻合。本文提出的数值计算方法和计算机程序可用于波纹环气膜冷却结构火焰筒的设计和验算,对于钻孔式气膜冷却结构或其它气膜冷却结构的火焰筒,只要对边界条件作出相应的修改,仍然可用。

关键词：气膜冷却火焰筒壁温热流数值解

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生物质快速裂解油蒸汽催化重整制氢研究进展

太阳能学报 2008年第6期29卷 745-750页

作者：安璐董长青杨勇平华北电力大学能源与动力工程学院电站设备状态检测与控制教育部重点实验室能源的安全与清洁利用北京市重点实验室北京102206

介绍了生物质快速裂解油制氢的研究发展过程并对其工艺过程、重整机理及催化剂研究进行了总结性的阐述,并进一步阐明目前该制氢方法存在的技术难点、研究重点以及未来发展方向。

关键词：生物质油氢快速裂解蒸汽重整

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电子稳像算法的速度与精度改进

计算机辅助设计与图形学学报 2018年第8期30卷 1543-1553页

作者：董常青程雪岷郝群清华大学深圳研究生院深圳518055 北京理工大学光电学院北京100081

电子稳像算法的目的是实时地去除视频拍摄过程中造成的随机不规则运动,以便后端的图像处理操作.针对处理时间以及精度方面进行研究提出了一种电子稳像算法.首先,实现了特征点个数的自适应提取,然后,提出并应用了满足凸优化条件的三点求... 详细信息

电子稳像算法的目的是实时地去除视频拍摄过程中造成的随机不规则运动,以便后端的图像处理操作.针对处理时间以及精度方面进行研究提出了一种电子稳像算法.首先,实现了特征点个数的自适应提取,然后,提出并应用了满足凸优化条件的三点求解和随机点校正来优化仿射矩阵,再对计算过程各阶段误差进行了优化控制,最后,通过局部提取运动目标区域进行动态补偿,将计算时间从20 ms减少到1 ms.实验结果表明,该算法每帧处理时间约为7 ms(不包括特征点提取部分),并具有较好的稳像效果.

关键词：电子稳像仿射矩阵全局补偿自适应阈值